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		<p class="post-meta">
		<time class="dt-published" datetime="2019-06-21T00:00:00-04:00" itemprop="datePublished">Friday, June 21, 2019
		</time>• by <span itemprop="author" itemscope itemtype="http://schema.org/Person"><span class="p-author h-card" itemprop="name">Ron Tarrant</span></span></p>
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		<div class="skew-line"></div>
		<h1 id="0047-spinbutton">0047: SpinButton</h1>

<p>This one’s both easy and tricky. Let me explain…</p>

<div class="screenshot-frame">
	<div class="frame-header">
		Results of this example:
	</div>
	<div class="frame-screenshot">
		<figure>
			<img id="img0" src="../images/screenshots/002_button/button_18.png" alt="Current example output" />		<!-- img# -->
			
			<!-- Modal for screenshot -->
			<div id="modal0" class="modal">																	<!-- modal# -->
				<span class="close0">&times;</span>															<!-- close# -->
				<img class="modal-content" id="img00" />															<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal0");														// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img0");															// img#
			var modalImg = document.getElementById("img00");													// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close0")[0];											// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>
			<figcaption>
			Current example output
			</figcaption>
		</figure>
	</div>

	<div class="frame-terminal">
		<figure class="right">
			<img id="img1" src="../images/screenshots/002_button/button_18_term.png" alt="Current example terminal output" />		<!-- img#, filename -->

			<!-- Modal for terminal shot -->
			<div id="modal1" class="modal">																				<!-- modal# -->
				<span class="close1">&times;</span>																		<!-- close# -->
				<img class="modal-content" id="img11" />																		<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal1");																	// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img1");																		// img#
			var modalImg = document.getElementById("img11");																// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close1")[0];														// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>

			<figcaption>
				Current example terminal output (click for enlarged view)
			</figcaption>
		</figure>
	</div>

	<div class="frame-footer">																								<!-- ------------- filename (below) --------- -->
		The code file for this example is available <a href="https://github.com/rontarrant/gtkd_demos/blob/master/002_button/button_18_spinbutton.d" target="_blank">here</a>.
	</div>
</div>

<p>Having a gander at the first example, you’ll see that the only new-ish bit is this:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">class</span> <span class="n">MySpinButton</span> <span class="p">:</span> <span class="n">SpinButton</span>
<span class="p">{</span>
	<span class="kt">double</span> <span class="n">minimum</span> <span class="p">=</span> <span class="p">-</span><span class="mi">50</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">maximum</span> <span class="p">=</span> <span class="mi">50</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">step</span> <span class="p">=</span> <span class="mi">2</span><span class="p">;</span>

	<span class="n">Adjustment</span> <span class="n">adjustment</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">initialValue</span> <span class="p">=</span> <span class="mi">4</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">pageIncrement</span> <span class="p">=</span> <span class="mi">8</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">pageSize</span> <span class="p">=</span> <span class="mi">0</span><span class="p">;</span>
	
	<span class="k">this</span><span class="p">()</span>
	<span class="p">{</span>
		<span class="k">super</span><span class="p">(</span><span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">step</span><span class="p">);</span>
		
		<span class="n">adjustment</span> <span class="p">=</span> <span class="k">new</span> <span class="n">Adjustment</span><span class="p">(</span><span class="n">initialValue</span><span class="p">,</span> <span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">step</span><span class="p">,</span> <span class="n">pageIncrement</span><span class="p">,</span> <span class="n">pageSize</span><span class="p">);</span>
		<span class="n">setAdjustment</span><span class="p">(</span><span class="n">adjustment</span><span class="p">);</span>
		<span class="n">addOnValueChanged</span><span class="p">(&amp;</span><span class="n">valueChanged</span><span class="p">);</span>
		
	<span class="p">}</span> <span class="c1">// this()</span>
	
	
	<span class="kt">void</span> <span class="n">valueChanged</span><span class="p">(</span><span class="n">SpinButton</span> <span class="n">sb</span><span class="p">)</span>
	<span class="p">{</span>
		<span class="n">writeln</span><span class="p">(</span><span class="n">getValue</span><span class="p">());</span>
		
	<span class="p">}</span> <span class="c1">// valueChanged()</span>


<span class="p">}</span> <span class="c1">// class MySpinButton</span>
</code></pre></div></div>

<p>One thing to notice here is that the <code class="language-plaintext highlighter-rouge">SpinButton</code> doesn’t work alone. It needs…</p>

<h2 id="the-adjustment">The Adjustment</h2>

<p>Technically, the <code class="language-plaintext highlighter-rouge">Adjustment</code> isn’t a <code class="language-plaintext highlighter-rouge">Widget</code> because it’s derived directly from <code class="language-plaintext highlighter-rouge">ObjectG</code>. This means that it doesn’t have a visual presence, but it does give you control over the range and behaviour of the <code class="language-plaintext highlighter-rouge">SpinButton</code>.</p>

<p><em>Note: The <code class="language-plaintext highlighter-rouge">Adjustment</code> also helps out a bunch of other <code class="language-plaintext highlighter-rouge">Widget</code>s including (but not limited to):</em></p>

<ul>
  <li><em>the <code class="language-plaintext highlighter-rouge">Container</code> and its offspring:</em>
    <ul>
      <li><em>the <code class="language-plaintext highlighter-rouge">Layout</code>,</em></li>
    </ul>
  </li>
  <li><em>the <code class="language-plaintext highlighter-rouge">ScaleButton</code>, and its child…</em>
    <ul>
      <li><em>the <code class="language-plaintext highlighter-rouge">VolumeButton</code>,</em></li>
    </ul>
  </li>
  <li><em>the <code class="language-plaintext highlighter-rouge">ScrolledWindow</code>, and</em></li>
  <li><em>the <code class="language-plaintext highlighter-rouge">Viewport</code>.</em></li>
</ul>

<p>In short, anything that needs adjusting. And the <code class="language-plaintext highlighter-rouge">Adjustment</code> is also the most complicated part of setting up and using a <code class="language-plaintext highlighter-rouge">SpinButton</code>.</p>

<p>At the top of the <code class="language-plaintext highlighter-rouge">MySpinButton</code> class definition, there’s a bunch of stuff initialized for use when instantiating the <code class="language-plaintext highlighter-rouge">Adjustment</code>, and as long as you keep these values sane, you’ll have very little trouble. These values are:</p>

<ul>
  <li><code class="language-plaintext highlighter-rouge">minimum</code> and <code class="language-plaintext highlighter-rouge">maximum</code> – straightforward, these are the upper and lower limits of the spinner,</li>
  <li><code class="language-plaintext highlighter-rouge">step</code> – the increment added to or subtracted from the current value each time the spinner buttons are clicked… or—while the <code class="language-plaintext highlighter-rouge">SpinButton</code> has focus—each time the up and down arrow keys are pressed,</li>
  <li><code class="language-plaintext highlighter-rouge">initialValue</code> – again straightforward, and then there’s…</li>
  <li><code class="language-plaintext highlighter-rouge">pageIncrement</code> – how much is added to or subtracted from the spinner’s current value when you hit the <em>Page-up</em> or <em>Page-down</em> keys, and</li>
  <li><code class="language-plaintext highlighter-rouge">pageSize</code>… Now, this is an odd one…</li>
</ul>

<h2 id="oddity-of-the-pagesize-argument">Oddity of the pageSize Argument</h2>

<p>With a <code class="language-plaintext highlighter-rouge">SpinButton</code>, the <code class="language-plaintext highlighter-rouge">Adjustment</code>’s <code class="language-plaintext highlighter-rouge">pageSize</code> is best set to ‘0.’</p>

<h2 id="variations-on-a-spinbutton--floating-point-values">Variations on a SpinButton – Floating Point Values</h2>

<div class="screenshot-frame">
	<div class="frame-header">
		Results of this example:
	</div>
	<div class="frame-screenshot">
		<figure>
			<img id="img2" src="../images/screenshots/002_button/button_19.png" alt="Current example output" />		<!-- img# -->
			
			<!-- Modal for screenshot -->
			<div id="modal2" class="modal">																<!-- modal# -->
				<span class="close2">&times;</span>														<!-- close# -->
				<img class="modal-content" id="img22" />														<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal2");													// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img2");														// img#
			var modalImg = document.getElementById("img22");												// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close2")[0];										// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>
			<figcaption>
			Current example output
			</figcaption>
		</figure>
	</div>

	<div class="frame-terminal">
		<figure class="right">
			<img id="img3" src="../images/screenshots/002_button/button_19_term.png" alt="Current example terminal output" /> 		<!-- img#, filename -->

			<!-- Modal for terminal shot -->
			<div id="modal3" class="modal">																			<!-- modal# -->
				<span class="close3">&times;</span>																	<!-- close# -->
				<img class="modal-content" id="img33" />																	<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal3");																// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img3");																	// img#
			var modalImg = document.getElementById("img33");															// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close3")[0];													// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>

			<figcaption>
				Current example terminal output (click for enlarged view)
			</figcaption>
		</figure>
	</div>

	<div class="frame-footer">																							<!--------- filename (below) ------------>
		The code file for this example is available <a href="https://github.com/rontarrant/gtkd_demos/blob/master/002_button/button_19_multiple_spinbuttons.d" target="_blank">here</a>.
	</div>
</div>

<p>In our second example, you’ll find (among others) the <code class="language-plaintext highlighter-rouge">FloatSpinButton</code> class:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">class</span> <span class="n">FloatSpinButton</span> <span class="p">:</span> <span class="n">SpinButton</span>
<span class="p">{</span>
	<span class="kt">float</span> <span class="n">minimum</span> <span class="p">=</span> <span class="p">-</span><span class="mf">1.0</span><span class="p">;</span>
	<span class="kt">float</span> <span class="n">maximum</span> <span class="p">=</span> <span class="mf">1.0</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">step</span> <span class="p">=</span> <span class="mf">.1</span><span class="p">;</span>

	<span class="n">Adjustment</span> <span class="n">adjustment</span><span class="p">;</span>
	<span class="kt">float</span> <span class="n">initialValue</span> <span class="p">=</span> <span class="mf">0.0</span><span class="p">;</span>
	<span class="kt">float</span> <span class="n">pageIncrement</span> <span class="p">=</span> <span class="mf">0.5</span><span class="p">;</span>
	<span class="kt">float</span> <span class="n">pageSize</span> <span class="p">=</span> <span class="mf">0.0</span><span class="p">;</span>
	
	<span class="k">this</span><span class="p">()</span>
	<span class="p">{</span>
		<span class="k">super</span><span class="p">(</span><span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">step</span><span class="p">);</span>
		<span class="n">adjustment</span> <span class="p">=</span> <span class="k">new</span> <span class="n">Adjustment</span><span class="p">(</span><span class="n">initialValue</span><span class="p">,</span> <span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">step</span><span class="p">,</span> <span class="n">pageIncrement</span><span class="p">,</span> <span class="n">pageSize</span><span class="p">);</span>
		<span class="n">setAdjustment</span><span class="p">(</span><span class="n">adjustment</span><span class="p">);</span>
		<span class="n">setWrap</span><span class="p">(</span><span class="kc">true</span><span class="p">);</span>
		
		<span class="n">addOnValueChanged</span><span class="p">(&amp;</span><span class="n">valueChanged</span><span class="p">);</span>
<span class="c1">//		addOnOutput(&amp;outputValue);</span>
		
	<span class="p">}</span> <span class="c1">// this()</span>

	<span class="kt">void</span> <span class="n">valueChanged</span><span class="p">(</span><span class="n">SpinButton</span> <span class="n">sb</span><span class="p">)</span>
	<span class="p">{</span>
		<span class="n">writeln</span><span class="p">(</span><span class="s">"Float Standard"</span><span class="p">,</span> <span class="n">getValue</span><span class="p">());</span>
		
	<span class="p">}</span> <span class="c1">// valueChanged()</span>

	
	<span class="kt">bool</span> <span class="n">outputValue</span><span class="p">(</span><span class="n">SpinButton</span> <span class="n">sb</span><span class="p">)</span>
	<span class="p">{</span>
		<span class="n">writeln</span><span class="p">(</span><span class="s">"Float Standard: "</span><span class="p">,</span> <span class="n">getValue</span><span class="p">());</span>
		
		<span class="k">return</span><span class="p">(</span><span class="kc">false</span><span class="p">);</span>
		
	<span class="p">}</span> <span class="c1">// outputValue()</span>
	
<span class="p">}</span> <span class="c1">// class FloatSpinButton</span>
</code></pre></div></div>

<p>The objective here is to use and show floating point values. But, notice that all the initialized parameters for the <code class="language-plaintext highlighter-rouge">Adjustment</code> are floats except for <code class="language-plaintext highlighter-rouge">step</code>. This is because of an oddity in the <code class="language-plaintext highlighter-rouge">Adjustment</code> object that seems to take two different forms, but rather than bore you with a long explanation, I’ll just give you the short version and jump right to the workaround for the current use-case…</p>

<p>The <code class="language-plaintext highlighter-rouge">SpinButton</code> has two signals you can hook up to:</p>

<ul>
  <li><code class="language-plaintext highlighter-rouge">onValueChanged</code>, and</li>
  <li><code class="language-plaintext highlighter-rouge">onOutput</code>.</li>
</ul>

<p>And there are a bunch of sane variable types you can use for the values:</p>

<ul>
  <li><code class="language-plaintext highlighter-rouge">double</code>,</li>
  <li><code class="language-plaintext highlighter-rouge">float</code>,</li>
  <li><code class="language-plaintext highlighter-rouge">int</code>,</li>
  <li><code class="language-plaintext highlighter-rouge">byte</code>, and</li>
  <li>you can even fake a <em>Boolean</em> by limiting the callback to checking for 0 or 1 only.</li>
</ul>

<p>For some reason, when combining certain variable types with a certain one or the other of the signals, clicking on the adjustment buttons will cause the signal to fire twice.</p>

<p><em>Note: This will also happen if you change the current value by typing into the in-built <code class="language-plaintext highlighter-rouge">Entry</code> and hitting</em> Enter. <em>It won’t double-fire</em> then, <em>but it will next time you click on one of the adjustment buttons. At present, I know of no way to avoid this, so if this behaviour will be noticable by your users, you may want to let them know so you don’t field a whole raft of bug reports on it.</em></p>

<h3 id="troubleshooting-a-spinbutton">Troubleshooting a SpinButton</h3>

<p>So, rule of thumb for using the <code class="language-plaintext highlighter-rouge">SpinButton</code> or any other widget using the <code class="language-plaintext highlighter-rouge">Adjustment</code>:</p>

<ol>
  <li>If you’re getting double signal firings with the <code class="language-plaintext highlighter-rouge">onValueChanged</code> signal, switch to the <code class="language-plaintext highlighter-rouge">onOutput</code> signal… and vice versa.</li>
  <li>If switching signals doesn’t help, try a different variable type (<code class="language-plaintext highlighter-rouge">int</code>, <code class="language-plaintext highlighter-rouge">byte</code>, <code class="language-plaintext highlighter-rouge">double</code>, <code class="language-plaintext highlighter-rouge">float</code>, etc.)</li>
</ol>

<h3 id="precision">Precision</h3>

<p>Now have a look at the first chunk of the <code class="language-plaintext highlighter-rouge">PrecisionSpinButton</code> class:</p>

<div class="language-d highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">class</span> <span class="n">PrecisionSpinButton</span> <span class="p">:</span> <span class="n">SpinButton</span>
<span class="p">{</span>
	<span class="kt">double</span> <span class="n">minimum</span> <span class="p">=</span> <span class="p">-</span><span class="mf">1.0</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">maximum</span> <span class="p">=</span> <span class="mf">1.0</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">step</span> <span class="p">=</span> <span class="mf">.0</span><span class="mo">01</span><span class="p">;</span>
	<span class="kt">uint</span> <span class="n">precision</span> <span class="p">=</span> <span class="mi">3</span><span class="p">;</span>

	<span class="n">Adjustment</span> <span class="n">adjustment</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">initialValue</span> <span class="p">=</span> <span class="mf">0.0</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">pageIncrement</span> <span class="p">=</span> <span class="mf">0.01</span><span class="p">;</span>
	<span class="kt">double</span> <span class="n">pageSize</span> <span class="p">=</span> <span class="mf">0.0</span><span class="p">;</span>
	
	<span class="k">this</span><span class="p">()</span>
	<span class="p">{</span>
		<span class="k">super</span><span class="p">(</span><span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">step</span><span class="p">);</span>
		<span class="n">adjustment</span> <span class="p">=</span> <span class="k">new</span> <span class="n">Adjustment</span><span class="p">(</span><span class="n">initialValue</span><span class="p">,</span> <span class="n">minimum</span><span class="p">,</span> <span class="n">maximum</span><span class="p">,</span> <span class="n">step</span><span class="p">,</span> <span class="n">pageIncrement</span><span class="p">,</span> <span class="n">pageSize</span><span class="p">);</span>
		<span class="n">setAdjustment</span><span class="p">(</span><span class="n">adjustment</span><span class="p">);</span>
		<span class="n">setDigits</span><span class="p">(</span><span class="n">precision</span><span class="p">);</span>

		<span class="n">addOnValueChanged</span><span class="p">(&amp;</span><span class="n">valueChanged</span><span class="p">);</span> <span class="c1">// NO double-fire</span>
<span class="c1">//		addOnOutput(&amp;outputValue); // double-fire</span>
		
	<span class="p">}</span> <span class="c1">// this()</span>
</code></pre></div></div>

<p>In the initialization section, we’ve got another variable: <code class="language-plaintext highlighter-rouge">precision</code>.</p>

<p>It’s used in the constructor with <code class="language-plaintext highlighter-rouge">setDigits()</code> to set the number of decimal places to show in the spinner.</p>

<h2 id="wrapping-up">Wrapping Up</h2>

<p>Now you know how to tame the <code class="language-plaintext highlighter-rouge">SpinButton</code> and <code class="language-plaintext highlighter-rouge">Adjustment</code> beasts.</p>

<h2 id="everything-but-the-kitchen-sink">Everything but the Kitchen Sink</h2>

<div class="screenshot-frame">
	<div class="frame-header">
		Results of this example:
	</div>
	<div class="frame-screenshot">
		<figure>
			<img id="img4" src="../images/screenshots/002_button/button_20.png" alt="Current example output" />		<!-- img# -->
			
			<!-- Modal for screenshot -->
			<div id="modal4" class="modal">																<!-- modal# -->
				<span class="close4">&times;</span>														<!-- close# -->
				<img class="modal-content" id="img44" />														<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal4");													// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img4");														// img#
			var modalImg = document.getElementById("img44");												// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close4")[0];										// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>
			<figcaption>
			Current example output
			</figcaption>
		</figure>
	</div>

	<div class="frame-terminal">
		<figure class="right">
			<img id="img5" src="../images/screenshots/002_button/button_20_term.png" alt="Current example terminal output" /> 		<!-- img#, filename -->

			<!-- Modal for terminal shot -->
			<div id="modal5" class="modal">																			<!-- modal# -->
				<span class="close5">&times;</span>																	<!-- close# -->
				<img class="modal-content" id="img55" />																	<!-- img## -->
				<div id="caption"></div>
			</div>
			
			<script>
			// Get the modal
			var modal = document.getElementById("modal5");																// modal#
			
			// Get the image and insert it inside the modal - use its "alt" text as a caption
			var img = document.getElementById("img5");																	// img#
			var modalImg = document.getElementById("img55");															// img##
			var captionText = document.getElementById("caption");

			img.onclick = function()
			{
			  modal.style.display = "block";
			  modalImg.src = this.src;
			  captionText.innerHTML = this.alt;
			}
			
			// Get the <span> element that closes the modal
			var span = document.getElementsByClassName("close5")[0];													// close#
			
			// When the user clicks on <span> (x), close the modal
			span.onclick = function()
			{ 
				modal.style.display = "none";
			}
			</script>

			<figcaption>
				Current example terminal output (click for enlarged view)
			</figcaption>
		</figure>
	</div>

	<div class="frame-footer">																							<!---------- filename (below) ---------->
		The code file for this example is available <a href="https://github.com/rontarrant/gtkd_demos/blob/master/002_button/button_20_spinbutton_experiments.d" target="_blank">here</a>.
	</div>
</div>

<p>And just for fun, I’ve included this third example with <code class="language-plaintext highlighter-rouge">Double-</code>, <code class="language-plaintext highlighter-rouge">Float-</code>, <code class="language-plaintext highlighter-rouge">Precision-</code>, <code class="language-plaintext highlighter-rouge">Int-</code>, <code class="language-plaintext highlighter-rouge">Byte-</code>, and that fake <code class="language-plaintext highlighter-rouge">BoolSpinButtons</code> I mentioned earlier, just to show how versatile this widget can be.</p>

<p><em>Note: The FloatSpinButton example in this file falls victim to GTK’s rounding error and so my recommendation is: don’t use the SpinButton for floating point values unless you’re prepared to deal with the rounding error yourself.</em></p>

<p>That’s it for this time around. Have a great day.</p>

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